The invention relates to a method for igniting a fuel/air mixture in a combustion chamber of a cyclically operating internal combustion engine using an ignition electrode constitutes a capacitance in cooperation with a wall of the combustion chamber that is at ground potential, wherein an electric oscillating circuit, which is connected to a secondary side of an electric DC/AC converter and the ignition electrode, is excited by way of a primary voltage applied to a primary side of the electric DC/AC converter, wherein the excitation of the oscillating circuit is controlled such that a corona discharge igniting the fuel/air mixture is created in the combustion chamber at the ignition electrode. According to the invention, the primary voltage is controlled to a specified setpoint value which is changed during the combustion duration of the corona discharge and is dependent upon the crankshaft angle and on at least one characteristic value of the fuel/air mixture.